Upgrades For The 90+ 300ZX TT Brake Systems

by Donn Vickrey IZCC#

For day-to-day driving, the stock ('90-'95) 300ZX brakes are more than adequate.
However, those that drive their Zs hard often find that repeated heavy
braking can lead to excessive brake fade and reduced stopping power. Road
racing, autocrossing, and just plain enthusiastic weekend driving can all
take your Zs braking system to its limits and beyond. Fortunately, there
are several brake system upgrades available to cure common braking woes.
All of the upgrades discussed below can be installed on turbo or non-turbo
(late model) 300s.

The easiest least and expensive upgrade is brake fluid. The Nissan factory
brake fluid is more than adequate for regular street use. However, repeated
hard stops can cause the brake fluid to boil, leading to brake fade and
possible failure. Using a high temperature synthetic or racing brake fluid
raises the temperature required to boil your brake fluid, providing extra
insurance against fade. However, there are two potential pitfalls to avoid.
First, do not use silicone based brake fluids in your Z; it can damage
your brake system components. Second, for street applications, use a brake
fluid with both a high wet boiling point and a high dry boiling point.
Certain racing fluids have very high dry boiling points, but lower wet boiling
points. Over time, your brake fluid takes on small amounts of water that
can lower the boiling point of your brake fluid. Racers avoid this problem
by bleeding their brakes often. I recommend Motul Dot 5 brake fluid or
Motul 600 racing brake fluid. Both have exceptionally high wet and dry
boiling points. The cost per bottle is about $8. One bottle is more than
enough for one Z.

While changing your brake fluid will go a long way toward minimizing brake
fade, the pedal can still feel mushy after repeated stops. One cause of
"mushy" brake pedals is expansion of the brake lines when exposed
to excessive heat. A set of stainless steel brake lines can remedy this
problem for about $65-$75 (parts only). The lines are relatively easy to
install yourself, or you can have them professionally installed for about
$50 (roughly 1 hour of labor). Have them put in upgraded brake fluid at
the same time to save on labor.

The last relatively inexpensive upgrade is a good set of semi-metallic,
or carbon fiber brake pads. Semi-metallic and carbon fiber pads can improve
braking performance significantly - decreasing 60-0 stopping distances by
as much as 10 feet. (A stock twin turbo can stop from 60-0 in approximately
125-130 feet.) . Moreover, while the stock pads lose stopping power when
subjected to temperature increases (from repeated stops), semi-metallic
and carbon fiber pads actually stop more effectively with increases in temperature
(up to a point). The only downside to these types of brake pads is that
they can decrease the life of your brake rotors since they retain more heat
in the pads themselves. The end result is an increase in the likelihood
of excessive run-off, i.e., warped rotors. I switched to carbon fiber
pads over 26,000 miles ago without any problems. This is surprising since
I am still running the original '90 ZXTT rotors that were known for warping
- and they have 54,000 miles on them! A good set of semi-metallic or carbon
fiber brake pads should cost approximately $150-$200 (front and rear).
For brake fluids, lines, and pads, I would contact either Porterfield Enterprises
(800-537-6842) or Stillen (714-540-5784).

Unfortunately, the brake upgrades mentioned above will not hold up under
serious road racing conditions. The problem, of course, is brake fade.
The stock rotors are not up to the demands of road racing. First, they
will fade in short order putting you and other competitors at risk. Second,
they will warp causing extreme vibration, even under moderate braking.
If you are going to run your Z on the track, you have only two options and
they are expensive! The first option is the Nissan competition brake package
that is standard equipment on the Japan-only Skyline and the 25th. Anniversary
SMZ. (This package is commonly referred to as the "Skyline brakes".)
The Skyline brakes will not fade no matter how hard you push them. However,
they will NOT improve stopping distances on the street and they list for,
are you sitting down, $2,000 (parts only). The second option is the Brembo
brake package offered by Stillen. The Brembo brake package is the ultimate
in performance brakes. Believe it or not, it is the brake system selected
by Ferrari for the F40! With these brakes, your car will stop like and
IMSA car without fade. The downside - they cost $2,600 (parts only). The
Brembo brake package is far superior to the Skyline package. However, the
Skyline brakes have one thing going for them - and very few people seem
to know about it. They only cost the dealer $1,000. So, there is substantial
room for negotiation! So, if you are friendly with your Nissan parts department,
that's the angle I'd try.